task/ta-npe-002-34 -- factor out pidfile creation into nparcel/based.py

nparcel/based.py
* new attributes script_name and pidfile

nparcel/bin/npcommsd
nparcel/bin/npexporterd
nparcel/bin/nploaderd
nparcel/bin/nppostcode
nparcel/bin/npprimaryelectd
* factor our hardwired pidfiles

nparcel/loader.py
* update the verify_postcodes() method to compare states with regular
  expressions